Persistent currents in annuli: Effects of disorder and Coulomb interaction

We investigate the persistent current of spinless electrons in a mesoscopic annulus threaded by a magnetic flux. As in the tight-binding systems, the excitations in the radial direction generate additional discontinuities in the persistent current, which are rounded off by disorder. The Coulomb interaction, the effects of which are investigated within the Hartree-Fock approximation, is found to suppress the persistent current in the presence of weak disorder. For strong disorder corresponding to the diffusive regime, the persistent current is enhanced by weak interactions.